Queen Rhaenys Targaryen is an unseen character mentioned in the second season. She lived and died centuries before the events of the series, and is not expected to appear. She was the sister and wife of Aegon the Conqueror and helped him in his invasion and conquest of Westeros three centuries before the events of the series. Rhaenys and Visenya were (simultaneously) the first Queens of the Andals and the First Men. She is a direct ancestor of Daenerys Targaryen and Jon Snow. Rhaenys is pronounced "Ray-niece".[1]

During the War of Conquest, she rode her dragon at the Field of Fire, where the Targaryens destroyed the largest army ever fielded against their troops and broke the bulk of resistance to their rule in Westeros.[1] However, Rhaenys ultimately perished along with her dragon in her attempt to conquer Dorne.[2]

Although she died long ago, the bloodline of Rhaenys Targaryen still lives in her two last living descendants: Daenerys Targaryen and Jon Snow.

Arya Stark, while posing as a common serving girl in Lannister-occupied Harrenhal, discusses the razing of the castle with Lord Tywin Lannister. She mentions Rhaenys and her dragon, but admits that Visenya was more of a hero of hers.[1]

In A Song of Ice and Fire, Rhaenys is said to have been the gentler, more playful and less serious of Aegon's sisters. While she rode her dragon in battle, she was not a warrior in the same way her brother and sister were, and unlike them did not possess a Valyrian steel sword.

She bore Aegon one son, Aenys, who later become the second King on the Iron Throne. After Aegon's death. Aenys was followed by Maegor the Cruel, but after his death Aenys's son, Jaehaerys inherited the throne. This means that all later members of House Targaryen, including Daenerys, are descended from Rhaenys.

In The World of Ice and Fire it is revealed that Aegon loved Rhaenys the most out of his sisters, spending ten nights with her for every one that he spent with Visenya. However, while Rhaenys was indeed the gentler of the two sisters, she was still a fierce warrior in her own right. She became a dragon-rider at a very young age and during the War of Conquest provided support for Orys Baratheon's assault on Storm's End. She also led the invasion of Dorne but the Dornish refused to give pitched battle, and resisted instead, through guerilla warfare. Frustrated, Rhaenys flew directly to Sunspear to demand Princess Meria's surrender. Meria instead informed her that, "This is Dorne. You are not wanted here, return at your peril." Rhaenys replied that she would return with "Fire and blood", but Meria simply replied, "Unbowed, Unbent, Unbroken". The Targaryen army withdrew from Dorne, leaving the country untaken.

As queen, Rhaenys actively led her brother's efforts to unite the realm into a solid and lasting entity. She organized marriages between the Great Houses to stop ancient feuds, having Lord Torrhen Stark's daughter marry the Lord of the Vale over the objections of her brothers. She also brought singers and artists to court so that they could make songs of the Targaryens and make them appear strong and present for the realm. She also cared for the smallfolk more than either her brother or her sister did. It appears that a rivalry between Rhaenys and Visenya for both Aegon's affections and for the best way to rule the realm divided the court.

In 4AC, Rhaenys joined Aegon I in his renewed efforts to conquer Dorne, however, this too proved unsuccessful. Rhaenys and her dragon, Meraxes, were slain during this war by a scorpion bolt. Aegon's fury and grief at the loss of his favourite wife led to him and Visenya burning all Dornish castles for two years in what was known as the Dragon's Wroth.

Rhaenys bore Aegon at least one son, Aenys, who succeeded his father on the Iron Throne. Although Visenya's son, Maegor, took the throne for himself upon Aenys's death, his cruel rule turned the whole realm against him and the nobility abandoned him in favour of Aenys's son; Rhaenys's grandson; Jaehaerys, who took the throne from his uncle. As such, Rhaenys's descendants ruled over the Seven Kingdoms instead of Visenya's and Daenerys is her direct descendant.